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Indexed by:期刊论文

Date of Publication:2012-08-01

Journal:10th International Symposium on Fusion Nuclear Technology (ISFNT)

Included Journals:SCIE、EI、CPCI-S

Volume:87

Issue:5-6

Page Number:782-786

ISSN No.:0920-3796

Key Words:Monte Carlo methods; Particle-in-cell method; Divertor; Graphite

Abstract:In order to investigate the origins of deposited carbon species in gaps, the simulations have been performed using a kinetic code system. At low plasma temperatures, the deposited carbon species mainly originate from top surfaces of the tile, while at high plasma temperatures the deposited carbon species are basically derived from side surfaces of the tile. A substantial variation of the deposition rate of carbon species originating from side surfaces is obtained due to physical sputtering and topography advantage. The deposited carbon species derived from top surfaces and side surfaces demonstrate different deposition characteristics for physical sputtering and chemical erosion: (i) for deposited carbon species from top surfaces, the deposition ratio for physical sputtering increases evidently and deposition rate virtually increases by one order of magnitude with increasing plasma temperature; and the deposition ratio for chemical erosion reduces correspondingly and deposition rate decreases gradually; (ii) for deposited carbon species from side surfaces, the deposited carbon species principally arise from physical sputtering; the deposition rates for chemical erosion are of the order of magnitude of 10(15) m(-2) s(-1) for all studied plasma temperatures, and the deposition rates for physical sputtering can be two to three orders of magnitude greater than that for chemical erosion. (C) 2012 Elsevier B.V. All rights reserved.